Random question for you as you’re knowledgable in this field. Do you think sound can ever travel in a straight line through some materials rather than radiate? (Higher vocal frequencies) An example being a flat panel TV mounted on the other side of a single brick thick wall finished with plaster, the TV can be heard more in the area of where that TV sits on the other side. If a decoupled full wall covering wasn’t possible, while not as effective, would a large decoupled, mass loaded panel (say 5mm rubber backed MDF) in that area actually help a little?

16:05 that's where isolation feet become your friend.

Never trust a contractor to sound isolate a space without strict supervision. I remember Erskine saying years ago that he had NEVER seen a sound isolation job where a mistake wasn't made! After finished our double stud theater a year ago, I believe him!

@PoesAcoustics

Жыл бұрын

Absolutely. And it’s not their fault. The contractors don’t understand this stuff if they have never done it before. They don’t think about intentionally building floppy walls.

Love the intro graphics. ( could be shorter imo ) Soundproofing.? .. should be standard building practice in apartments.. good lord. I need it.

@psyphonyxaudio

Жыл бұрын

Also loving how the sun tracks across the left side of the frame =) Thanks for the clarity on this stuff. LOTS of people do need this .. whether they admit it or not. =)

Excellent video. I am building a home theater in the garage. The theater is on a concrete slab. I am building a room within a room for noise isolation. I like playing high level of base in the theater. What is the best way to isolate to base that travels in the concrete floor into the next room? Kinetic RIM ?. In your theater, you are using Husman Frame isolator. I am trying to find more information about Husman Frame isolator. Can you give me the website address? Thank-you.

I have a home theater in my basement (20w x 25L x 8h). Would it be better to reduce the sqft of the theater in order to isolate the room (13w x 20L x 8)?

I didn’t find this to be a long video but it was an interesting and informative video. I have a flooring company and before tearing out the hardwood on the main floor. I am trying to determine the best way for me to isolate the wooden sub floor. My current thoughts are acoustic sealant along perimeter and spray foam. 3/8” of self leveller ( 3 lbs per s/f). 5 mm of recycled rubber sound isolation membrane installed on floor & behind baseboard with thinset. Next, install Ditra Heat or Ditra Heat Duo installed with a glue. Finally, install 60”x120”x6mm porcelain or sintered stone floor tile with 1/4” backer rod around perimeter. My home is worth about $550 - $600 per s/f. Excluding labour & the flooring. The leveller, glue & membranes would retail around $15 s/f. Am I better off to apply another layer of plywood with green glue?

@PoesAcoustics

Жыл бұрын

Check out Maxxon sound isolation mats for guides on how to handle sound isolation assemblies with self leveling floors. The poured floor is a great option, but you actually need to float the subfloor and not the flooring on top. You want to use an acoustic rated product like Maxxon sells under the self leveling concrete or gypsum flooring. This is substantially better. I believe they specify a minimum one inch topping. As for the worth, that is up to you. For most people this would be the most expensive way to isolate sound through the floor. However it is also one of the more effective. There are better isolation layers such as Kinetic RIM, but the Maxxon product is very good for a lower profile design. My cost to have someone install this on a job is typically a $5000 minimum show up fee and that often covers a 300 square ft area pretty close. However much beyond that and I believe it’s another $50 a square foot. If you can install this with your company for $10-$20 a square foot, go for it. If you ever install self leveling flooring in a building that needs sound isolation, use the method I am showing here. It should be better by quite a bit with minimal additional cost. Unfortunately a lot of hotels and apartments are done incorrectly and fail to actually meet isolation requirements for such buildings.

@PoesAcoustics

Жыл бұрын

Green glue and two layers of subfloor wouldn’t hurt but probably won’t help a lot. The mat will do the most decoupling. The mass needs to double to substantially improve things. The concrete is a lot more massive than the plywood.

@shawnperepelytz6397

Жыл бұрын

@@PoesAcoustics thank you Mathew. This helps a lot.

My room is 12’x14’ with a 5’x4’ closet that will be the equipment room. Two of the walls are brick exterior walls with no windows. Is there any advantage to treating the exterior walls or should I just treat the interior walls?

@PoesAcoustics

Жыл бұрын

If budget is a major concern and you want to keep sound in, rather than keep sound out, focus on the interior walls and ceiling. If you are trying to make the room quieter, concrete walls aren’t that quite. They still need to be treated too.

Bass is super hard to stop. I'll consider double concrete partitions for my next room (like the Hahn theater) if I ever get the chance to build it!

@PoesAcoustics

Жыл бұрын

Concrete is not necessarily better. You always need resilience. I don’t think Hahn has concrete walls either. There is good reason not to do that. I don’t believe that Keith has ever shared how he built the walls but they appear from the pics I’ve seen to be layered with things like MLV, drywall, and other materials. Concrete board might have been used but keep in mind that is only slightly denser than drywall. Hahn used the best but most expensive build techniques like the concrete decoupled floor on which the walls were then built. It’s a 7” or more thick floor in total. Without a means to decouple the inner concrete wall, you would likely find that it performs significantly worse than a steel stud partition with decoupling. It’s possible to decouple the concrete partition but I suspect once you see the price you will move on to other options. Far cheaper to do what I did and performance is very similar. In fact the floating floor assembly I did has similar performance to the concrete decouple slab approach. It’s slightly worse and it’s likely that adding mass via additional layers would bring that back. One of the big problems you run into at very low frequencies is that the room operates as a pressure vessel. It’s the rigidity and overall sealed nature of the room and the isolation of serious vibrational energy that prevents its transfer. You end up needing inches of articulation for the isolators. You also need a very rigid structure. Concrete is very rigid so it is good, but a layered wall can be made equally rigid. The biggest issue with concrete is that it’s very hard to damp. Layerings various materials with damping compounds can help alleviate this. You need the damping because the wall resonance ends up sitting at a key bass range where it can lead to high sound transmittance over a wide range. A good octave or so. One way to understand the issue here is to look at the flanking limits and construction methods of test labs. The older labs were built with two layers of concrete block. Riverbank is a good example and their flanking limit is very low. Less than 60STC. The highest I am aware of is NWAA labs. Their flanking limit I believe is around STC 78. Their walls are formed with concrete board and drywall along with dual steel studs. How did they achieve such a high STC including such good low frequency isolation? The walls have a 20” airgap.

Maybe, I misunderstood your explanation of the sound isolation methods that you used in your house. I didn't hear anything about decoupling your walls and ceiling. Was that part of the air gap that you mentioned?

@PoesAcoustics

Жыл бұрын

Hushframe is decoupling. All of the walls, ceiling, and floor are decoupled.

@PoesAcoustics

Жыл бұрын

I have some older videos that actually show my theaters sound isolation techniques. This video wasn’t meant to reflect necessarily what I did. The exterior walls are 2x6 stud walls with hush frame isolators and two layers of drywall adhered with a VE adhesive. The exterior is two layers of 3/4” plywood and is stuccoed. The interior walls are double stud walls. The top plate has hushframe isolators to decouple. The baseplate sits on a rubber decoupler. The inner shell wall is built on top of the decoupled floor. Ceiling is hushframe decouplers and two layers of drywall. The floor is a layer of 3/4” subfloor, a hushframe decouple and fiberglass insulation, then two layers of 3/4” subfloor plywood. On top of that is a sound isolation mat and LVP. The door is the Isodoor HD LF. I’ve done sound transmission loss measurements and converted to STC. It comes in around STC 62. I have completed more work on flanking paths so it may be higher now. I’ll do final testing when the room is complete. I’ve mentioned in other videos that a number of companies provide misleading or even inaccurate information about the STC capabilities of their products. In practice, STC 65+ is very hard to achieve and lab rated assemblies claiming well in excess of this are likely not accurate. Most labs have flanking limits in the 50’s to 60’s which makes testing STC 70+ totally impossible and totally nonsense. Which is all to say, achieving STC 62 on a decoupled double stud wall with 4 layers of drywall is actually very typical of such assemblies.

@TheArthilles

Жыл бұрын

@@PoesAcoustics Ah! That's what I was looking for. It's crazy that you were able to achieve that high of an STC and the room above still has vibrations. If you built a room within a room instead of using hushframe, do you believe that would have solved that problem? And if you had the ceiling height to sacrifice.

@TheArthilles

Жыл бұрын

@@PoesAcoustics Also, will you be going over more of your "soundproofing" steps in future videos? HVAC comes to mind.

@TheArthilles

Жыл бұрын

Sorry I should finish the video first. I only got half way through before I started asking about more "soundproof" stuff.